MHB -2.2.4 find general solution xy'+2y=e^x

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The general solution to the differential equation xy' + 2y = e^x is derived by first dividing through by x, resulting in y' + (2/x)y = (e^x/x). The integrating factor u(x) is calculated as u(x) = x^2. After multiplying the entire equation by x^2, it simplifies to (x^2 y)' = xe^x, which is then integrated to yield x^2 y = e^x(x - 1) + c. Finally, dividing by x^2 gives the solution y = (e^x/x) - (e^x/x^2) + (c/x^2).
karush
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$\textsf{find the general solution}$
$$xy'+2y=e^x$$
$\textsf{divide thru by x}$
$$y' +\frac{2}{x}y=\frac{e^x}{x}$$
$\textsf{Find u(x)}$
$$\displaystyle u(x)=\exp\int\frac{2}{x} \, dx=e^{\ln x^2}=x^2$$
$\textsf{so far anyway..}$
 
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karush said:
$\textsf{find the general solution}$
$$xy'+2y=e^x$$
$\textsf{divide thru by x}$
$$y' +\frac{2}{x}y=\frac{e^x}{x}$$
$\textsf{Find u(x)}$
$$\displaystyle u(x)=\exp\int\frac{2}{x} \, dx=e^{\ln x^2}=x^2$$
$\textsf{multiply thru with $x^2$}$
$x^2 y' +2xy=xe^x$
$(x^2 y)'=xe^x$
$\textsf{integrate}$
$\displaystyle x^2 y=\int xe^x \, dx =e^x(x-1)+c$
$\textsf{divide thru by $x^2$}$
$\displaystyle y=\frac{e^x}{x}-\frac{e^x}{x^2}+\frac{c}{x^2}$
hopefully
 

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